iOS - UICollectionView spacing still there when set to 0 - How to set with no spacing between cells

Question

I have a simple UICollectionView which I have set with 0 spacing in InterfaceBuilder but when I populate the collection view with cells there is still some spacing. Is there

Answer 1

You have to create custom UICollectionViewLayout.

Space between the cells will be equal to cellSpacing.

final class CustomFlowLayout: UICollectionViewFlowLayout {

    let cellSpacing: CGFloat = 0

    override func layoutAttributesForElements(in rect: CGRect) -> [UICollectionViewLayoutAttributes]? {
        if let attributes = super.layoutAttributesForElements(in: rect) {
            for (index, attribute) in attributes.enumerated() {
                if index == 0 { continue }
                let prevLayoutAttributes = attributes[index - 1]
                let origin = prevLayoutAttributes.frame.maxX
                if (origin + cellSpacing + attribute.frame.size.width < self.collectionViewContentSize.width) {
                    attribute.frame.origin.x = origin + cellSpacing
                }
            }
            return attributes
        }
        return nil
    }

}